a41aa11f7ad3a946f8958747cb8e0380c4192125
[samba.git] / source3 / libsmb / clientgen.c
1 /* 
2    Unix SMB/CIFS implementation.
3    SMB client generic functions
4    Copyright (C) Andrew Tridgell 1994-1998
5    Copyright (C) Jeremy Allison 2007.
6    
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11    
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16    
17    You should have received a copy of the GNU General Public License
18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #include "includes.h"
22
23 /*******************************************************************
24  Setup the word count and byte count for a client smb message.
25 ********************************************************************/
26
27 int cli_set_message(char *buf,int num_words,int num_bytes,bool zero)
28 {
29         if (zero && (num_words || num_bytes)) {
30                 memset(buf + smb_size,'\0',num_words*2 + num_bytes);
31         }
32         SCVAL(buf,smb_wct,num_words);
33         SSVAL(buf,smb_vwv + num_words*SIZEOFWORD,num_bytes);
34         smb_setlen(buf,smb_size + num_words*2 + num_bytes - 4);
35         return (smb_size + num_words*2 + num_bytes);
36 }
37
38 /****************************************************************************
39  Change the timeout (in milliseconds).
40 ****************************************************************************/
41
42 unsigned int cli_set_timeout(struct cli_state *cli, unsigned int timeout)
43 {
44         unsigned int old_timeout = cli->timeout;
45         cli->timeout = timeout;
46         return old_timeout;
47 }
48
49 /****************************************************************************
50  Change the port number used to call on.
51 ****************************************************************************/
52
53 void cli_set_port(struct cli_state *cli, int port)
54 {
55         cli->port = port;
56 }
57
58 /****************************************************************************
59  convenience routine to find if we negotiated ucs2
60 ****************************************************************************/
61
62 bool cli_ucs2(struct cli_state *cli)
63 {
64         return ((cli->capabilities & CAP_UNICODE) != 0);
65 }
66
67
68 /****************************************************************************
69  Read an smb from a fd ignoring all keepalive packets.
70  The timeout is in milliseconds
71
72  This is exactly the same as receive_smb except that it never returns
73  a session keepalive packet (just as receive_smb used to do).
74  receive_smb was changed to return keepalives as the oplock processing means this call
75  should never go into a blocking read.
76 ****************************************************************************/
77
78 static ssize_t client_receive_smb(struct cli_state *cli, size_t maxlen)
79 {
80         size_t len;
81
82         for(;;) {
83                 NTSTATUS status;
84
85                 set_smb_read_error(&cli->smb_rw_error, SMB_READ_OK);
86
87                 status = receive_smb_raw(cli->fd, cli->inbuf, cli->bufsize,
88                                         cli->timeout, maxlen, &len);
89                 if (!NT_STATUS_IS_OK(status)) {
90                         DEBUG(10,("client_receive_smb failed\n"));
91                         show_msg(cli->inbuf);
92
93                         if (NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) {
94                                 set_smb_read_error(&cli->smb_rw_error,
95                                                    SMB_READ_EOF);
96                                 return -1;
97                         }
98
99                         if (NT_STATUS_EQUAL(status, NT_STATUS_IO_TIMEOUT)) {
100                                 set_smb_read_error(&cli->smb_rw_error,
101                                                    SMB_READ_TIMEOUT);
102                                 return -1;
103                         }
104
105                         set_smb_read_error(&cli->smb_rw_error, SMB_READ_ERROR);
106                         return -1;
107                 }
108
109                 /*
110                  * I don't believe len can be < 0 with NT_STATUS_OK
111                  * returned above, but this check doesn't hurt. JRA.
112                  */
113
114                 if ((ssize_t)len < 0) {
115                         return len;
116                 }
117
118                 /* Ignore session keepalive packets. */
119                 if(CVAL(cli->inbuf,0) != SMBkeepalive) {
120                         break;
121                 }
122         }
123
124         if (cli_encryption_on(cli)) {
125                 NTSTATUS status = cli_decrypt_message(cli);
126                 if (!NT_STATUS_IS_OK(status)) {
127                         DEBUG(0, ("SMB decryption failed on incoming packet! Error %s\n",
128                                 nt_errstr(status)));
129                         cli->smb_rw_error = SMB_READ_BAD_DECRYPT;
130                         return -1;
131                 }
132         }
133
134         show_msg(cli->inbuf);
135         return len;
136 }
137
138 /****************************************************************************
139  Recv an smb.
140 ****************************************************************************/
141
142 bool cli_receive_smb(struct cli_state *cli)
143 {
144         ssize_t len;
145
146         /* fd == -1 causes segfaults -- Tom (tom@ninja.nl) */
147         if (cli->fd == -1)
148                 return false; 
149
150  again:
151         len = client_receive_smb(cli, 0);
152         
153         if (len > 0) {
154                 /* it might be an oplock break request */
155                 if (!(CVAL(cli->inbuf, smb_flg) & FLAG_REPLY) &&
156                     CVAL(cli->inbuf,smb_com) == SMBlockingX &&
157                     SVAL(cli->inbuf,smb_vwv6) == 0 &&
158                     SVAL(cli->inbuf,smb_vwv7) == 0) {
159                         if (cli->oplock_handler) {
160                                 int fnum = SVAL(cli->inbuf,smb_vwv2);
161                                 unsigned char level = CVAL(cli->inbuf,smb_vwv3+1);
162                                 if (!cli->oplock_handler(cli, fnum, level)) {
163                                         return false;
164                                 }
165                         }
166                         /* try to prevent loops */
167                         SCVAL(cli->inbuf,smb_com,0xFF);
168                         goto again;
169                 }
170         }
171
172         /* If the server is not responding, note that now */
173         if (len < 0) {
174                 DEBUG(0, ("Receiving SMB: Server stopped responding\n"));
175                 close(cli->fd);
176                 cli->fd = -1;
177                 return false;
178         }
179
180         if (!cli_check_sign_mac(cli, cli->inbuf)) {
181                 /*
182                  * If we get a signature failure in sessionsetup, then
183                  * the server sometimes just reflects the sent signature
184                  * back to us. Detect this and allow the upper layer to
185                  * retrieve the correct Windows error message.
186                  */
187                 if (CVAL(cli->outbuf,smb_com) == SMBsesssetupX &&
188                         (smb_len(cli->inbuf) > (smb_ss_field + 8 - 4)) &&
189                         (SVAL(cli->inbuf,smb_flg2) & FLAGS2_SMB_SECURITY_SIGNATURES) &&
190                         memcmp(&cli->outbuf[smb_ss_field],&cli->inbuf[smb_ss_field],8) == 0 &&
191                         cli_is_error(cli)) {
192
193                         /*
194                          * Reflected signature on login error. 
195                          * Set bad sig but don't close fd.
196                          */
197                         cli->smb_rw_error = SMB_READ_BAD_SIG;
198                         return true;
199                 }
200
201                 DEBUG(0, ("SMB Signature verification failed on incoming packet!\n"));
202                 cli->smb_rw_error = SMB_READ_BAD_SIG;
203                 close(cli->fd);
204                 cli->fd = -1;
205                 return false;
206         };
207         return true;
208 }
209
210 /****************************************************************************
211  Read the data portion of a readX smb.
212  The timeout is in milliseconds
213 ****************************************************************************/
214
215 ssize_t cli_receive_smb_data(struct cli_state *cli, char *buffer, size_t len)
216 {
217         NTSTATUS status;
218
219         set_smb_read_error(&cli->smb_rw_error, SMB_READ_OK);
220
221         status = read_socket_with_timeout(
222                 cli->fd, buffer, len, len, cli->timeout, NULL);
223         if (NT_STATUS_IS_OK(status)) {
224                 return len;
225         }
226
227         if (NT_STATUS_EQUAL(status, NT_STATUS_END_OF_FILE)) {
228                 set_smb_read_error(&cli->smb_rw_error, SMB_READ_EOF);
229                 return -1;
230         }
231
232         if (NT_STATUS_EQUAL(status, NT_STATUS_IO_TIMEOUT)) {
233                 set_smb_read_error(&cli->smb_rw_error, SMB_READ_TIMEOUT);
234                 return -1;
235         }
236
237         set_smb_read_error(&cli->smb_rw_error, SMB_READ_ERROR);
238         return -1;
239 }
240
241 static ssize_t write_socket(int fd, const char *buf, size_t len)
242 {
243         ssize_t ret=0;
244
245         DEBUG(6,("write_socket(%d,%d)\n",fd,(int)len));
246         ret = write_data(fd,buf,len);
247
248         DEBUG(6,("write_socket(%d,%d) wrote %d\n",fd,(int)len,(int)ret));
249         if(ret <= 0)
250                 DEBUG(0,("write_socket: Error writing %d bytes to socket %d: ERRNO = %s\n",
251                         (int)len, fd, strerror(errno) ));
252
253         return(ret);
254 }
255
256 /****************************************************************************
257  Send an smb to a fd.
258 ****************************************************************************/
259
260 bool cli_send_smb(struct cli_state *cli)
261 {
262         size_t len;
263         size_t nwritten=0;
264         ssize_t ret;
265         char *buf_out = cli->outbuf;
266         bool enc_on = cli_encryption_on(cli);
267
268         /* fd == -1 causes segfaults -- Tom (tom@ninja.nl) */
269         if (cli->fd == -1)
270                 return false;
271
272         cli_calculate_sign_mac(cli, cli->outbuf);
273
274         if (enc_on) {
275                 NTSTATUS status = cli_encrypt_message(cli, cli->outbuf,
276                                                       &buf_out);
277                 if (!NT_STATUS_IS_OK(status)) {
278                         close(cli->fd);
279                         cli->fd = -1;
280                         cli->smb_rw_error = SMB_WRITE_ERROR;
281                         DEBUG(0,("Error in encrypting client message. Error %s\n",
282                                 nt_errstr(status) ));
283                         return false;
284                 }
285         }
286
287         len = smb_len(buf_out) + 4;
288
289         while (nwritten < len) {
290                 ret = write_socket(cli->fd,buf_out+nwritten,len - nwritten);
291                 if (ret <= 0) {
292                         if (enc_on) {
293                                 cli_free_enc_buffer(cli, buf_out);
294                         }
295                         close(cli->fd);
296                         cli->fd = -1;
297                         cli->smb_rw_error = SMB_WRITE_ERROR;
298                         DEBUG(0,("Error writing %d bytes to client. %d (%s)\n",
299                                 (int)len,(int)ret, strerror(errno) ));
300                         return false;
301                 }
302                 nwritten += ret;
303         }
304
305         if (enc_on) {
306                 cli_free_enc_buffer(cli, buf_out);
307         }
308
309         /* Increment the mid so we can tell between responses. */
310         cli->mid++;
311         if (!cli->mid)
312                 cli->mid++;
313         return true;
314 }
315
316 /****************************************************************************
317  Send a "direct" writeX smb to a fd.
318 ****************************************************************************/
319
320 bool cli_send_smb_direct_writeX(struct cli_state *cli,
321                                 const char *p,
322                                 size_t extradata)
323 {
324         /* First length to send is the offset to the data. */
325         size_t len = SVAL(cli->outbuf,smb_vwv11) + 4;
326         size_t nwritten=0;
327         struct iovec iov[2];
328
329         /* fd == -1 causes segfaults -- Tom (tom@ninja.nl) */
330         if (cli->fd == -1) {
331                 return false;
332         }
333
334         if (client_is_signing_on(cli)) {
335                 DEBUG(0,("cli_send_smb_large: cannot send signed packet.\n"));
336                 return false;
337         }
338
339         iov[0].iov_base = cli->outbuf;
340         iov[0].iov_len = len;
341         iov[1].iov_base = CONST_DISCARD(char *, p);
342         iov[1].iov_len = extradata;
343
344         nwritten = write_data_iov(cli->fd, iov, 2);
345         if (nwritten < (len + extradata)) {
346                 close(cli->fd);
347                 cli->fd = -1;
348                 cli->smb_rw_error = SMB_WRITE_ERROR;
349                 DEBUG(0,("Error writing %d bytes to client. (%s)\n",
350                          (int)(len+extradata), strerror(errno)));
351                 return false;
352         }
353
354         /* Increment the mid so we can tell between responses. */
355         cli->mid++;
356         if (!cli->mid)
357                 cli->mid++;
358         return true;
359 }
360
361 /****************************************************************************
362  Setup basics in a outgoing packet.
363 ****************************************************************************/
364
365 void cli_setup_packet_buf(struct cli_state *cli, char *buf)
366 {
367         uint16 flags2;
368         cli->rap_error = 0;
369         SIVAL(buf,smb_rcls,0);
370         SSVAL(buf,smb_pid,cli->pid);
371         memset(buf+smb_pidhigh, 0, 12);
372         SSVAL(buf,smb_uid,cli->vuid);
373         SSVAL(buf,smb_mid,cli->mid);
374
375         if (cli->protocol <= PROTOCOL_CORE) {
376                 return;
377         }
378
379         if (cli->case_sensitive) {
380                 SCVAL(buf,smb_flg,0x0);
381         } else {
382                 /* Default setting, case insensitive. */
383                 SCVAL(buf,smb_flg,0x8);
384         }
385         flags2 = FLAGS2_LONG_PATH_COMPONENTS;
386         if (cli->capabilities & CAP_UNICODE)
387                 flags2 |= FLAGS2_UNICODE_STRINGS;
388         if ((cli->capabilities & CAP_DFS) && cli->dfsroot)
389                 flags2 |= FLAGS2_DFS_PATHNAMES;
390         if (cli->capabilities & CAP_STATUS32)
391                 flags2 |= FLAGS2_32_BIT_ERROR_CODES;
392         if (cli->use_spnego)
393                 flags2 |= FLAGS2_EXTENDED_SECURITY;
394         SSVAL(buf,smb_flg2, flags2);
395 }
396
397 void cli_setup_packet(struct cli_state *cli)
398 {
399         cli_setup_packet_buf(cli, cli->outbuf);
400 }
401
402 /****************************************************************************
403  Setup the bcc length of the packet from a pointer to the end of the data.
404 ****************************************************************************/
405
406 void cli_setup_bcc(struct cli_state *cli, void *p)
407 {
408         set_message_bcc(cli->outbuf, PTR_DIFF(p, smb_buf(cli->outbuf)));
409 }
410
411 /****************************************************************************
412  Initialise credentials of a client structure.
413 ****************************************************************************/
414
415 void cli_init_creds(struct cli_state *cli, const char *username, const char *domain, const char *password)
416 {
417         fstrcpy(cli->domain, domain);
418         fstrcpy(cli->user_name, username);
419         pwd_set_cleartext(&cli->pwd, password);
420         if (!*username) {
421                 cli->pwd.null_pwd = true;
422         }
423
424         DEBUG(10,("cli_init_creds: user %s domain %s\n", cli->user_name, cli->domain));
425 }
426
427 /****************************************************************************
428  Set the signing state (used from the command line).
429 ****************************************************************************/
430
431 void cli_setup_signing_state(struct cli_state *cli, int signing_state)
432 {
433         if (signing_state == Undefined)
434                 return;
435
436         if (signing_state == false) {
437                 cli->sign_info.allow_smb_signing = false;
438                 cli->sign_info.mandatory_signing = false;
439                 return;
440         }
441
442         cli->sign_info.allow_smb_signing = true;
443
444         if (signing_state == Required) 
445                 cli->sign_info.mandatory_signing = true;
446 }
447
448 /****************************************************************************
449  Initialise a client structure. Always returns a malloc'ed struct.
450 ****************************************************************************/
451
452 struct cli_state *cli_initialise(void)
453 {
454         struct cli_state *cli = NULL;
455
456         /* Check the effective uid - make sure we are not setuid */
457         if (is_setuid_root()) {
458                 DEBUG(0,("libsmb based programs must *NOT* be setuid root.\n"));
459                 return NULL;
460         }
461
462         cli = TALLOC_ZERO_P(NULL, struct cli_state);
463         if (!cli) {
464                 return NULL;
465         }
466
467         cli->port = 0;
468         cli->fd = -1;
469         cli->cnum = -1;
470         cli->pid = (uint16)sys_getpid();
471         cli->mid = 1;
472         cli->vuid = UID_FIELD_INVALID;
473         cli->protocol = PROTOCOL_NT1;
474         cli->timeout = 20000; /* Timeout is in milliseconds. */
475         cli->bufsize = CLI_BUFFER_SIZE+4;
476         cli->max_xmit = cli->bufsize;
477         cli->outbuf = (char *)SMB_MALLOC(cli->bufsize+SAFETY_MARGIN);
478         cli->inbuf = (char *)SMB_MALLOC(cli->bufsize+SAFETY_MARGIN);
479         cli->oplock_handler = cli_oplock_ack;
480         cli->case_sensitive = false;
481         cli->smb_rw_error = SMB_READ_OK;
482
483         cli->use_spnego = lp_client_use_spnego();
484
485         cli->capabilities = CAP_UNICODE | CAP_STATUS32 | CAP_DFS;
486
487         /* Set the CLI_FORCE_DOSERR environment variable to test
488            client routines using DOS errors instead of STATUS32
489            ones.  This intended only as a temporary hack. */    
490         if (getenv("CLI_FORCE_DOSERR"))
491                 cli->force_dos_errors = true;
492
493         if (lp_client_signing()) 
494                 cli->sign_info.allow_smb_signing = true;
495
496         if (lp_client_signing() == Required) 
497                 cli->sign_info.mandatory_signing = true;
498                                    
499         if (!cli->outbuf || !cli->inbuf)
500                 goto error;
501
502         memset(cli->outbuf, 0, cli->bufsize);
503         memset(cli->inbuf, 0, cli->bufsize);
504
505
506 #if defined(DEVELOPER)
507         /* just because we over-allocate, doesn't mean it's right to use it */
508         clobber_region(FUNCTION_MACRO, __LINE__, cli->outbuf+cli->bufsize, SAFETY_MARGIN);
509         clobber_region(FUNCTION_MACRO, __LINE__, cli->inbuf+cli->bufsize, SAFETY_MARGIN);
510 #endif
511
512         /* initialise signing */
513         cli_null_set_signing(cli);
514
515         cli->initialised = 1;
516
517         return cli;
518
519         /* Clean up after malloc() error */
520
521  error:
522
523         SAFE_FREE(cli->inbuf);
524         SAFE_FREE(cli->outbuf);
525         SAFE_FREE(cli);
526         return NULL;
527 }
528
529 /****************************************************************************
530  Close all pipes open on this session.
531 ****************************************************************************/
532
533 void cli_nt_pipes_close(struct cli_state *cli)
534 {
535         while (cli->pipe_list != NULL) {
536                 /*
537                  * No TALLOC_FREE here!
538                  */
539                 talloc_free(cli->pipe_list);
540         }
541 }
542
543 /****************************************************************************
544  Shutdown a client structure.
545 ****************************************************************************/
546
547 void cli_shutdown(struct cli_state *cli)
548 {
549         cli_nt_pipes_close(cli);
550
551         /*
552          * tell our peer to free his resources.  Wihtout this, when an
553          * application attempts to do a graceful shutdown and calls
554          * smbc_free_context() to clean up all connections, some connections
555          * can remain active on the peer end, until some (long) timeout period
556          * later.  This tree disconnect forces the peer to clean up, since the
557          * connection will be going away.
558          *
559          * Also, do not do tree disconnect when cli->smb_rw_error is SMB_DO_NOT_DO_TDIS
560          * the only user for this so far is smbmount which passes opened connection
561          * down to kernel's smbfs module.
562          */
563         if ( (cli->cnum != (uint16)-1) && (cli->smb_rw_error != SMB_DO_NOT_DO_TDIS ) ) {
564                 cli_tdis(cli);
565         }
566         
567         SAFE_FREE(cli->outbuf);
568         SAFE_FREE(cli->inbuf);
569
570         cli_free_signing_context(cli);
571         data_blob_free(&cli->secblob);
572         data_blob_free(&cli->user_session_key);
573
574         if (cli->fd != -1) {
575                 close(cli->fd);
576         }
577         cli->fd = -1;
578         cli->smb_rw_error = SMB_READ_OK;
579
580         TALLOC_FREE(cli);
581 }
582
583 /****************************************************************************
584  Set socket options on a open connection.
585 ****************************************************************************/
586
587 void cli_sockopt(struct cli_state *cli, const char *options)
588 {
589         set_socket_options(cli->fd, options);
590 }
591
592 /****************************************************************************
593  Set the PID to use for smb messages. Return the old pid.
594 ****************************************************************************/
595
596 uint16 cli_setpid(struct cli_state *cli, uint16 pid)
597 {
598         uint16 ret = cli->pid;
599         cli->pid = pid;
600         return ret;
601 }
602
603 /****************************************************************************
604  Set the case sensitivity flag on the packets. Returns old state.
605 ****************************************************************************/
606
607 bool cli_set_case_sensitive(struct cli_state *cli, bool case_sensitive)
608 {
609         bool ret = cli->case_sensitive;
610         cli->case_sensitive = case_sensitive;
611         return ret;
612 }
613
614 /****************************************************************************
615 Send a keepalive packet to the server
616 ****************************************************************************/
617
618 bool cli_send_keepalive(struct cli_state *cli)
619 {
620         if (cli->fd == -1) {
621                 DEBUG(3, ("cli_send_keepalive: fd == -1\n"));
622                 return false;
623         }
624         if (!send_keepalive(cli->fd)) {
625                 close(cli->fd);
626                 cli->fd = -1;
627                 DEBUG(0,("Error sending keepalive packet to client.\n"));
628                 return false;
629         }
630         return true;
631 }
632
633 /**
634  * @brief: Collect a echo reply
635  * @param[in] req       The corresponding async request
636  *
637  * There might be more than one echo reply. This helper pulls the reply out of
638  * the data stream. If all expected replies have arrived, declare the
639  * async_req done.
640  */
641
642 static void cli_echo_recv_helper(struct async_req *req)
643 {
644         struct cli_request *cli_req;
645         uint8_t wct;
646         uint16_t *vwv;
647         uint16_t num_bytes;
648         uint8_t *bytes;
649         NTSTATUS status;
650
651         status = cli_pull_reply(req, &wct, &vwv, &num_bytes, &bytes);
652         if (!NT_STATUS_IS_OK(status)) {
653                 async_req_error(req, status);
654                 return;
655         }
656
657         cli_req = talloc_get_type_abort(req->private_data, struct cli_request);
658
659         if ((num_bytes != cli_req->data.echo.data.length)
660             || (memcmp(cli_req->data.echo.data.data, bytes,
661                        num_bytes) != 0)) {
662                 async_req_error(req, NT_STATUS_INVALID_NETWORK_RESPONSE);
663                 return;
664         }
665
666         cli_req->data.echo.num_echos -= 1;
667
668         if (cli_req->data.echo.num_echos == 0) {
669                 client_set_trans_sign_state_off(cli_req->cli, cli_req->mid);
670                 async_req_done(req);
671                 return;
672         }
673
674         return;
675 }
676
677 /**
678  * @brief Send SMBEcho requests
679  * @param[in] mem_ctx   The memory context to put the async_req on
680  * @param[in] ev        The event context that will call us back
681  * @param[in] cli       The connection to send the echo to
682  * @param[in] num_echos How many times do we want to get the reply?
683  * @param[in] data      The data we want to get back
684  * @retval The async request
685  */
686
687 struct async_req *cli_echo_send(TALLOC_CTX *mem_ctx, struct event_context *ev,
688                                 struct cli_state *cli, uint16_t num_echos,
689                                 DATA_BLOB data)
690 {
691         uint16_t vwv[1];
692         uint8_t *data_copy;
693         struct async_req *result;
694         struct cli_request *req;
695
696         SSVAL(vwv, 0, num_echos);
697
698         data_copy = (uint8_t *)talloc_memdup(mem_ctx, data.data, data.length);
699         if (data_copy == NULL) {
700                 return NULL;
701         }
702
703         result = cli_request_send(mem_ctx, ev, cli, SMBecho, 0, 1, vwv, 0,
704                                   data.length, data.data);
705         if (result == NULL) {
706                 TALLOC_FREE(data_copy);
707                 return NULL;
708         }
709         req = talloc_get_type_abort(result->private_data, struct cli_request);
710
711         client_set_trans_sign_state_on(cli, req->mid);
712
713         req->data.echo.num_echos = num_echos;
714         req->data.echo.data.data = talloc_move(req, &data_copy);
715         req->data.echo.data.length = data.length;
716
717         req->recv_helper.fn = cli_echo_recv_helper;
718
719         return result;
720 }
721
722 /**
723  * Get the result out from an echo request
724  * @param[in] req       The async_req from cli_echo_send
725  * @retval Did the server reply correctly?
726  */
727
728 NTSTATUS cli_echo_recv(struct async_req *req)
729 {
730         return async_req_simple_recv(req);
731 }
732
733 /**
734  * @brief Send/Receive SMBEcho requests
735  * @param[in] mem_ctx   The memory context to put the async_req on
736  * @param[in] ev        The event context that will call us back
737  * @param[in] cli       The connection to send the echo to
738  * @param[in] num_echos How many times do we want to get the reply?
739  * @param[in] data      The data we want to get back
740  * @retval Did the server reply correctly?
741  */
742
743 NTSTATUS cli_echo(struct cli_state *cli, uint16_t num_echos, DATA_BLOB data)
744 {
745         TALLOC_CTX *frame = talloc_stackframe();
746         struct event_context *ev;
747         struct async_req *req;
748         NTSTATUS status = NT_STATUS_NO_MEMORY;
749
750         if (cli->fd_event != NULL) {
751                 /*
752                  * Can't use sync call while an async call is in flight
753                  */
754                 cli_set_error(cli, NT_STATUS_INVALID_PARAMETER);
755                 goto fail;
756         }
757
758         ev = event_context_init(frame);
759         if (ev == NULL) {
760                 goto fail;
761         }
762
763         req = cli_echo_send(frame, ev, cli, num_echos, data);
764         if (req == NULL) {
765                 goto fail;
766         }
767
768         while (req->state < ASYNC_REQ_DONE) {
769                 event_loop_once(ev);
770         }
771
772         status = cli_echo_recv(req);
773
774  fail:
775         TALLOC_FREE(frame);
776         return status;
777 }
778
779 /**
780  * Is the SMB command able to hold an AND_X successor
781  * @param[in] cmd       The SMB command in question
782  * @retval Can we add a chained request after "cmd"?
783  */
784 bool is_andx_req(uint8_t cmd)
785 {
786         switch (cmd) {
787         case SMBtconX:
788         case SMBlockingX:
789         case SMBopenX:
790         case SMBreadX:
791         case SMBwriteX:
792         case SMBsesssetupX:
793         case SMBulogoffX:
794         case SMBntcreateX:
795                 return true;
796                 break;
797         default:
798                 break;
799         }
800
801         return false;
802 }